The company (organisation) was formed as a separately listed subsidiary in November 1997 under the name of Singapore Bus Service, although it can trace its history back to the formation of Singapore Bus Service in 1973 with the merger of three bus companies. On 1 November 2001, the company's name was changed to SBS Transit Limited to reflect its status as a bus and rail operator. It is a subsidiary of ComfortDelGro.

Singapore Bus Service (SBS) was initially formed in 1973 with the merger of three private bus companies. The government-sanctioned merger was undertaken to improve service standards of the bus transport system.

With the shift towards the creation of multi-modal transport companies, Singapore Bus Service changed its name to ComfortDelGro in November 1997. Bus operations were hived-off to a fully owned subsidiary called Singapore Bus Services Limited, which was separately listed on the Singapore Exchange.

In November 2001, Singapore Bus Services Limited was renamed as SBS Transit Limited when the company formally became a multi-modal transport operator with the impending opening of the Sengkang LRT Line.

SBS Transit operates 75% of the scheduled bus market share in Singapore with more than 300 bus services and a total fleet of more than 3,000 buses. It consists of the largest depots, Ang Mo Kio, Bedok North, Hougang, Loyang and Soon Lee.

The latest additions to the bus fleet are the Volvo B9TL (Wright Eclipse Gemini 2) double decker buses and the Mercedes-Benz Citaro buses. Quoted from a press release by SBS Transit on 9 July 2012 stated that, SBS Transit will add 1,000 more buses which consist of 550 Volvo B9TL (Wright Eclipse Gemini 2) double decker buses and 450 Mercedes-Benz Citaro buses by 2015. Delivery of these buses are ongoing since January 2013.[3] Wheelchair-accessible buses– Mercedes-Benz Citaro buses and Volvo B9TL (Wright Eclipse Gemini 2) double decker buses–have been used for Bus Service Enhancement Programme (BSEP) since 17 September 2012.[4]

On 1 July 2014, SBS Transit announced that they have placed orders worth $311 million for 665 Euro V buses, all of which come with wheelchair-friendly features. The newest addition comprises 250 single deck Mercedes-Benz Citaro buses and 415 double deck Volvo B9TL (Wright Eclipse Gemini 2) buses.[5][6] Of the new buses, 296 will be funded by the Government under the Bus Service Enhancement Programme (BSEP). All the new buses will be delivered by 2017. The latest services to be added into the network as part of BSEP were services 41 and 140, which made their debut on 14 December 2014.[7]

SBS Transit operates many different types of bus routes and bus services, taking up the majority of the pie of Singapore's duopoly bus system in almost all areas of Singapore, with the notable exception of the North and Northwest areas, where bus services are mainly run by its competitor, SMRT Buses.

The North East Line is the third line in Singapore, and also the world's first fully underground and automated rapid transit line. The line is 20 km long with 16 stations. The operating license was given to SBS Transit in order to foster competition with SMRT Trains and to create multi-modal public transport companies, each specialising in their own district. The tender spans from 2003 to 2033.

A major breakdown occurred on 15 March 2012 affected 90,000 commuters due to a power supply problem in the tunnel at Outram Park station.[9] This caused train services to be disrupted, between 06:30 to 16:35, on NEL between Harbourfront and Dhoby Ghaut stations. Subsequently, the Land Transport Authority (LTA) intends to impose financial penalties amounting to S$400,000 (approximately US$315,000) on SBS Transit for the disruption.[10]